On Thu, May 30, 2019 at 07:08:45PM +0200, Martin Jambor wrote:
> Interesting, I was also puzzled for a moment. But notice that:
>
> int main ()
> {
> _Float128 x = 18446744073709551617.5f128;
> _Float128 y = __builtin_roundf128 (x);
> }
>
> behaves as expected... the difference is of course the suffix pegged to
> the literal constant (see
> https://gcc.gnu.org/onlinedocs/gcc-9.1.0/gcc/Floating-Types.html).
>
> I would also expect GCC to use a larger type if a constant does not fit
> into a double, but apparently that does not happen. I would have to
> check but it is probably the right behavior according to the standard.
6.4.4.2/4: "An unsuffixed floating constant has type double." I don't
think your suggestion would be okay?
Segher
